AIM: To describe an optimal route to the Braun anastomosis including the use of retrieval-balloon-assisted enterography.METHODS: Patients who received a Billroth II gastroenterostomy (n = 109) and a Billroth II gastroenterostomy with Braun anastomosis (n = 20) between January 2009 and May 2013 were analyzed in this study. Endoscopic retrograde cholangiopancreatography (ERCP) was performed under fluoroscopic control using a total length of 120 cm oblique-viewing duodenoscope with a 3.7-mm diameter working channel. For this procedure, we used a triple-lumen retrieval balloon catheter in which a 0.035-inch guidewire could be inserted into the "open-channel" guidewire lumen while the balloon could be simultaneously injected and inflated through the other 2 lumens.RESULTS: For the patients with Billroth II gastroenterostomy and Braun anastomosis, successful access to the papilla was gained in 17 patients (85%) and there was therapeutic success in 16 patients (80%). One patient had afferent loop perforation, but postoperative bleeding did not occur. For Billroth II gastroenterostomy, there was failure in accessing the papilla in 15 patients (13.8%). ERCP was unsuccessful because of tumor infiltration (6 patients), a long afferent loop (9 patients), and cannulation failure (4 patients). The papilla was successfully accessed in 94 patients (86.2%), and there was therapeutic success in 90 patients (82.6%). Afferent loop perforation did not occur in any of these patients. One patient had hemorrhage 2 h after ERCP, which was successfully managed with conservative treatment.CONCLUSION: Retrieval-balloon-assisted enterography along an optimal route may improve the ERCP success rate after Billroth II gastroenterostomy and Braun anastomosis.